THE EXAMS POINTDouble circulation: trace one complete route
Begin at the centre. Explore a branch, explain its connection, then test your recall. Tap any branch heading to fold or expand it.
In recall mode, focus or tap a branch to reveal its explanation. Numbered branches follow a simplified process; read them in order.
Double circulation: trace one complete route
01 · Body → venae cavae → right atrium
Oxygen-poor systemic venous blood returns to the heart.
02 · Right ventricle → pulmonary artery
The right side pumps blood towards the lungs.
03 · Lung capillaries
Gas exchange adds oxygen and removes carbon dioxide.
04 · Pulmonary veins → left atrium
Oxygen-rich blood returns from the lungs.
05 · Left ventricle → aorta → body
The left side supplies the systemic circulation.
Connect the branches
In a complete pulmonary-plus-systemic route, blood passes through the heart twice. Valves support one-way flow.
Avoid the exam trap
Arteries carry blood away from the heart; they are not defined by oxygen content.
Test yourself: Why is the pulmonary artery an exception to the usual oxygen rule?
It carries blood away from the right ventricle to the lungs, but that blood is oxygen-poor.
A concise revision aid with simplified connections. It supports the full chapter and primary references; it does not replace them.